Considerable effort has been expended in the past to develop mouthwashes and treatment agents which have some chemical activity useful in retarding plaque, caries, and calculus formation. Conventional mouthwashes, purportedly designed to kill or control microbes which contribute to plaque and caries development, are not only generally ineffective as oral bacteriocides or bacteriostats but may even promote infection by oral bacteria and fungus by removing cornified epithelial layers and thereby allowing the escape of fluids and defensive cells which normally combat infection.